The present invention relates to an apparatus of forming an electrode with gas assist deposition using a charged particle beam and a method of using the same.
In recent years, a technology of fabricating an integrated circuit is remarkable, and an integration degree is significantly promoted. Further, in order to realize more highly integrated formation, basic researches on molecule elements and single electron elements have been promoted.
In developing the molecule element, in order to grasp properties of the molecule, it is necessary to measure a conduction property thereof. Hence, electrodes having a gap of a molecule size (about 1 nm) therebetween are fabricated, a molecule is interposed in the gap, and various properties are measured.
As a method of fabricating a narrow gap, for example, there is a method of using a sputtering etching technology of a focused ion beam. According thereto, an electric wire comprising a conductive substance formed on an insulating film is etched by using a focused ion beam and an argon ion beam to form electrodes having a width of a gap of 5 nm therebetween (refer to Nonpatent Reference 1).
[Nonpatent Reference 1] “Fabrication of nano-gap electrodes for measuring electrical properties of organic molecules using a focused ion beam”, Solid Thin Film 438-439 (2003) 374-377
However, according to the method of fabricating a narrow gap by using a sputtering etching of a focused ion beam, there poses a problem that a lower limit of a width of the gap formed is rectified by a beam diameter of the focused ion beam.
It is a problem of the invention to resolve the above-described problem to form a pair of electrodes having an extremely narrow gap width equal to or smaller than a beam diameter of a focused ion beam.